Gas Burner for a Gas Hob, Gas Cooker, and Method for Operating a Gas Hob

ABSTRACT

A gas burner for a gas cooktop has a gas burner body with gas outlet openings. A thermogenerator is arranged above the gas burner body, advantageously arranged concentrically relative to said gas burner body and with the same shape and size, wherein the thermogenerator is heated by said gas burner body. The thermogenerator bears against a cooler pot base by way of its upper face. The thermogenerator generates electrical energy which is used to operate a control of the gas cooktop and which can be stored.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of DE 102010042872.8 filed on Oct. 25, 2010, the contents of which are expressly incorporated herein by reference in its entirety.

FIELD OF APPLICATION

The invention generally relates to a gas burner for a gas cooktop, to a gas cooktop which is provided with said gas burner, and also to a method for operating a gas cooktop of this kind.

BACKGROUND

Thermogenerators are known per se for generating electrical energy. To this end, a hot side of the thermogenerator is subjected to the action of heat or heated, while the heat is drawn or output on a cold side. However, the degree of efficiency of a thermogenerator of this kind is usually only 3% to 5%, and therefore the amount of thermal energy that has to be conducted by the thermogenerator is considerably more than the amount of electrical energy obtained. On the other hand, a sufficient amount of thermal energy is available in many applications.

DE 10 2007 058 945 A1 discloses installing a thermogenerator on a gas burner in a gas cooktop. There, the thermal energy which is conducted by the thermogenerator is diverted away toward the gas cooktop. The cold side of the thermogenerator therefore faces the gas cooktop which firstly heats up, this being negative. Furthermore, this thermal energy is lost to the cooking process.

SUMMARY

The disclosure is generally directed to providing a gas burner, a gas cooktop and also a method for operating a gas burner of this kind as cited in the introductory part and with which problems which arise in the prior art can be avoided and, in particular, an efficient and structurally simple way of generating electrical energy at a gas burner of a gas cooktop by means of a thermogenerator is provided.

Advantageous and preferred refinements of the invention are the subject matter of the further claims and will be explained in the text which follows. In the process, some of the features cited in the text which follows are explained only in respect of the gas burner, the gas cooktop or one of the methods. However, irrespective of this, they are intended to be applicable to the gas burner, the gas cooktop and also the methods. The wording of the claims is incorporated in the content of the description by express reference.

According to one embodiment, a gas burner, which has a gas burner body which is customary per se and has gas outlet openings, has a thermogenerator arranged above said gas burner body. The thermogenerator can be particularly advantageously arranged concentrically relative to the gas burner body and/or have the same shape or the same or a similar size. As a result, it is possible for the hot side of the thermogenerator to be subjected to the action of thermal energy by the gas burner body itself, this thermal energy otherwise being introduced at the top into a cooking vessel which is placed above the gas burner. The cold side of the thermogenerator is, as it were, cooled by this cooking vessel. This occurs either due to the emission of heat to the base of the pot which is located above said thermogenerator or else, in a preferred refinement of the invention, on account of the cold side of the thermogenerator bearing against the base of the pot. This can be achieved in a particularly preferred manner by flexible or resilient holding means which hold the thermogenerator above the gas burner body and primarily push said thermogenerator against the lower face of the cooking vessel.

These and further features can be gathered not only from the claims but also from the description and the drawings, where the individual features can be realized in each case by themselves or in combination in the form of subcombinations in an embodiment of the invention and in other fields and can constitute advantageous and inherently patentable embodiments for which protection is claimed here. The subdivision of the application into individual sections and subheadings do not restrict the general validity of the statements made thereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention are schematically illustrated in the drawings and will be explained in greater detail in the text which follows. In the drawings:

FIG. 1 shows a first embodiment of a gas burner in a gas cooktop as a single-ring burner with a heat conduction element and a thermogenerator above it,

FIG. 2 shows a further embodiment of a gas burner with a thermogenerator which is part of a pot support, and

FIG. 3 shows a further embodiment of gas burner which is in the form of a two-ring burner.

DETAILED DESCRIPTION

It has been found that although a thermogenerator which has been put in position directly on the upper face of the gas burner body can absorb the thermal energy very well, it is considered to be more expedient to use radiant heat for the input of thermal energy and to design the thermogenerator with its cold side directly against the lower face of the pot for output purposes since, under certain circumstances, it is mechanically relatively difficult to simultaneously achieve abutment against the lower face of a pot which has been placed on in order to draw away the thermal energy on the cold side. A spring device may be provided for this purpose and can be designed in various ways but which, for temperature resistance purposes, is advantageously composed of metal and therefore can be, for example, in the form of a plate spring or helical spring provided on the upper face of the gas burner body.

A thermogenerator is advantageously in the form of a disk, with its diameter being considerably larger than its thickness or height. The thermogenerator is particularly advantageously arranged approximately parallel to the plane of the gas burner openings. This usually also means that it is arranged parallel to a pot base, this being advantageous primarily for good abutment against said pot base.

In one embodiment, provision may be made for the thermogenerator to be larger than the gas burner body or to laterally protrude beyond said gas burner body. Therefore, the gas flames emerging from the gas outlet openings can be used at least partially to heat up the hot side of the thermogenerator, so that the thermal energy can be introduced in a very effective manner. If the hot side of the thermogenerator is located very close to the upper face of the gas burner body, the transfer of the thermal energy is likewise very easily possible and it is possible for this transfer to be achieved even without the gas flame having to directly reach the thermogenerator.

As an alternative embodiment to the above-described options, a lower first heat conduction element can be arranged between the gas burner or the gas burner body and the thermogenerator. This heat conduction element is advantageously likewise in the form of a disk and arranged such that it is approximately parallel to the plane of the gas burner openings, that is to say, preferably also parallel to the thermogenerator, and at a distance therefrom. The first heat conduction element is intended to bear directly against the hot side of the thermogenerator for the best possible introduction of thermal energy. The first heat conduction element can also be larger than the gas burner body, for example as was described above, for a possible design of the thermogenerator, and therefore the gas flames directly heat the heat conduction element. To this end, said heat conduction element can project laterally beyond the gas burner body by at least 10% of the diameter of the gas burner body or of a ring of the gas burner openings, preferably by a maximum of 20%. Therefore, the lower first heat conduction element can, as it were, capture a portion of the thermal energy and pass it to the thermogenerator, this thermal energy being generated by the gas burner by means of the gas flames in order to thus heat the pot, which is placed on, via its pot base.

In another, provision can be made for the lower first heat conduction element to have, in its edge region, holes and/or recesses in the form of incisions with projections located between them. An edge of this kind of the first heat conduction element can be substantially in the form of a toothed wheel. This can serve to heat the projecting projections, as it were, to a particularly pronounced extent by the gas flames running beneath them. Depending on the power configuration, the holes or recesses can be situated over the gas flames, and therefore these flames can burn through substantially between the projections and, as a secondary effect, heat up the projections. This ensures that a large portion of the thermal energy which is generated by the gas burner is introduced into the pot base. As an alternative, provision can be made for the projections to be situated directly over the gas flames or the gas burner openings which form said gas flames. However, said projections are intended to protrude laterally beyond the gas burner body only to such an extent that the projections are heated to a pronounced extent for introducing thermal energy into the thermogenerator at a level which is sufficient at a low power level only when the gas flames are small in accordance with this low power level. If a higher power level is selected, the gas flames burn more vigorously or are longer and extend far beyond the projections which then continue to be heated. However, a large portion of the thermal energy which is generated by the gas flames is then passed, as desired, to the pot base.

In a yet further embodiment, a further upper second heat conduction element can be provided above or on the upper face of the thermogenerator, that is to say on the cold side. The heat conduction element is particularly advantageously likewise in the form of a disk, as are the thermogenerator and the above-described first heat conduction element. The heat conduction element can advantageously also be approximately the same size as the thermogenerator itself, or alternatively also somewhat larger again, similarly to the first heat conduction element. Therefore, the thermal energy can be transferred particularly effectively from the cold side of the thermogenerator to the pot base. However, the upper second heat conduction element should not be excessively large, so that the gas flames which are generated by the gas burner can continue to ensure sufficiently effective and rapid heating of the pot base. The second heat conduction element also serves for the improved conduction of heat, in this case away from the thermogenerator to the pot base.

In another embodiment of a gas burner, said gas burner is a so-called single-ring burner with a single gas burner body and a single group of gas burner openings in said gas burner body, said gas burner openings being provided on the outer circumference of said gas burner body in the form of a ring, as is customary.

A spring device can advantageously also be provided on a removable cover of a gas burner body, for example also equally as a unit together with the thermogenerator itself. This unit may comprise a cover for the gas burner body, possibly with a spring and the thermogenerator and also possibly including the above-described heat conduction elements, and can therefore be fitted and removed. This is advantageous when only one single such unit is intended to be provided for the gas cooktop according to the invention for cost reasons, and therefore said unit is then used in each case on the gas burner which is to be operated.

In another embodiment, the gas burner is in the form of a two-ring burner. The gas burner has an inner gas burner body and an outer gas burner body. In this case, the thermogenerator is arranged above the inner gas burner body since this is usually always in operation when the gas burner is operating. A gas flame is advantageously formed at the inner gas burner body in a manner which cannot be regulated, but rather which always operates with a thermal power which is designed in such a way that the thermogenerator generates a required electrical power. A gas flame is formed at the outer gas burner body in a manner which can be regulated, and therefore, if the intention is to operate with a power which goes beyond the thermal power of the first inner gas burner body, the second outer gas burner body is, as it were, switched on. This can ensure that, during operation of this two-ring burner, the required thermal energy is always present at the thermogenerator and therefore the required electrical power is generated. Operation with a minimum thermal power at the gas burner body is also applicable for the above-described single-ring burner in any case.

In a further embodiment, it is possible to design the thermogenerator itself as a pot support or as part of a pot support of this kind. To this end, the thermogenerator can be arranged on the gas burner such that it cannot move in the vertical direction, so that it is also stable, in order to be able to place a pot on it. The thermogenerator is advantageously arranged centrally over the gas burner body and has outwardly leading connections to support means on the gas cooktop beneath it, advantageously three to provide standing stability. Therefore, yet further bearing points for the pot are provided in an outer region around the thermogenerator, so that said pot does not bear only on the thermogenerator. In this case, the thermogenerator is intended to be thermally insulated as well as possible from the other parts of the pot support, so that the thermal energy which is to be drawn from the cold side is introduced into the pot as far as possible. The situation of too much thermal energy being drawn from the heating process of the pot can be avoided as a result.

As has already been described, the thermogenerator can advantageously be designed in a removable manner on its own or as a unit together with part of the gas burner body, for example the cover of the gas burner body. This is possible, firstly, for a case in which it is not required at all, for example because the gas cooktop is connected to a mains power supply (e.g., household power) system. Furthermore, this can result primarily in a thermogenerator of this kind not being provided on each gas burner of a gas cooktop but rather fewer or, particularly advantageously, only one single thermogenerator being provided.

In the case of a gas cooktop according to one, provision is made for the thermogenerator to have an electrical connection to a power supply means of the gas cooktop. This electrical connection is intended to exhibit sufficient thermal resistance to advantageously be routed laterally away from the thermogenerator, downward, to the gas cooktop. Since it is inevitably also acted on by the gas flames from the gas burner in the process, care should be taken that it also has sufficient thermal insulation in this respect. Firstly, said electrical connection is intended to cross the gas flame as far as possible above said gas flame. Secondly, electrical and thermal insulation means can have a glass fiber fabric, and plastic or the like can be dispensed with, or have only plastic with a high thermal resistance, such as silicone or the like.

The controller of the gas cooktop is advantageously an electronic controller which has, for example, in addition to program sequences which can be stored, touch-operated switches which are electronically triggered and evaluated. Furthermore, energy store in the form of a rechargeable battery is advantageously contained in the power supply or said power supply has a rechargeable battery. Therefore, any excess electrical energy from the thermogenerator which may have been generated can be stored for starting operation of the gas burner or of the gas cooktop, this being required, on account of there being an electronic controller, before the thermogenerator can actually generate electrical energy.

In an advantageous embodiment, the gas cooktop can have electrical ignition devices for igniting the gas burners. Furthermore, devices such as flame monitoring means or the like can be provided.

In another advantageous embodiment, a gas cooktop can have both single-ring burners and two-ring burners, in particular as have been described above.

In a yet further embodiment, the gas cooktop can be designed such that it can be operated completely without an electrical connection to a mains power supply system. Under certain circumstances, it can even be designed entirely without the option of being electrically connected or without a connection cable. In this case, the electrical energy for operating the abovementioned control means and possibly also the gas valves or other functional devices is drawn solely from said rechargeable battery. In this case, the rechargeable battery also has to be kept charged as far as possible. A gas cooktop of this kind can advantageously also be operated in locations or in an environment which have/has a gas supply, for example by gas cylinders, but are/is not connected to the mains power supply system. Therefore, the concepts disclosed herein are also suitable for portable gas cooktops, for example for camping.

It may be advantageous, specifically for charging the above-mentioned rechargeable battery, to design the electrical power of the thermogenerator to be higher than the power actually acutely required in each case by the controller of the gas cooktop or electrical gas valves or the like. In this way, excess electrical energy from the thermogenerator can be stored in the energy storage means for a further operation.

As has been discussed above, electrically or electronically controlled gas valves are advantageously provided in the gas cooktop. These gas valves can be designed such that, in the case of an above-described two-ring burner, only the inner gas burner is ignited and burns with a specific thermal power at a minimum power setting. This thermal power is designed such that the thermogenerator operates effectively and can advantageously generate the required electrical power for supplying the electronic controller or operates with as high a degree of efficiency as possible. Therefore, in addition to power being supplied to the gas cooktop itself, said energy storage means can also be charged. When the gas valve of the inner gas burner is opened further, said inner gas burner burns with a higher thermal power, with the outer gas burner then being ignited with the further increase and it therefore being possible for the thermal power of said outer gas burner to be fully regulated.

Therefore, in a method disclosed herein for operating an above-described gas cooktop, it is not only possible to obtain electrical energy by means of the thermogenerator, without an excessive amount of thermal energy for heating the pot being drawn, but rather, further functions can also be achieved by the thermogenerator. For example, for a pot identification function, a check can be made as to whether a pot is placed over the gas burner by the thermoelectric voltage being monitored. If the cold side of the thermogenerator is specifically not cooled by a pot base which has been placed on or put in position when the gas burner is operating, no thermoelectric voltage or only a very low thermoelectric voltage is produced at the thermogenerator. Since a controller can check whether the gas burner is operating and, with reference to the position of the gas valve, it can also check the gas throughflow rate and the thermal power at which said gas burner is operating. This information can be used to identify that no pot has even been placed on. This can be evaluated by the controller as a pot being missing and possibly be output in the form of a signal or the like.

In a further embodiment of a method for operating an above-described gas cooktop, the thermoelectric voltage at the thermogenerator can again be monitored and therefore the temperature of the pot base of the pot which has been placed on can be monitored. This temperature determines, specifically, the temperature on the cold side of the thermogenerator and therefore the thermoelectric voltage generated. In this case, provision can be made, after a relatively long phase of an approximately constant temperature of the pot base owing to an approximately constant thermoelectric voltage during operation of the gas burner, for the control means to draw the conclusion that the pot which has been placed on has boiled dry if there is a subsequent rapid increase in temperature due to an increase in the thermoelectric voltage. Therefore, the temperature of its pot base increases to a great extent. The controller can then output a corresponding signal and, for example, switch off the gas burner.

In the case of a yet further method disclosed herein for operating a gas cooktop with a two-ring burner, provision may be made for the control means to detect the thermal power at the gas burner. To this end, the gas throughflow rate to the gas burner can be monitored advantageously by detecting the passage or an open position of the gas valve. This can, in turn, be compared with the electrical power which is output by the thermogenerator or the thermoelectric voltage. The result of this comparison can be used to at least approximately determine the temperature of a pot base, in particular the relative profile of said temperature. The measurement variables or the detected and determined values can advantageously be used to regulate cooking processes.

Turning now to the figures, FIG. 1 illustrates a gas cooktop 11 with a cooktop plate 12. According to one embodiment, said gas cooktop has a gas burner 14 which comprises a gas burner body 15 with gas outlet openings 16 which are arranged in said gas burner body in the form of a ring, as is customary. The gas burner 14 is supplied with gas by means of a gas feed line 18, the passage of gas through said gas feed line being regulated by an electrically controllable gas valve 19. The gas valve 19 is controlled by a controller 20 of the gas cooktop 11. This controller 20 can be designed either only for this gas burner 14 alone or else for all the gas burners or, advantageously, for the entire gas cooktop 11.

A heat conduction element 23 is held above the gas burner 14 on the upper face of the gas burner 14 or the gas burner body 15, which upper face can be formed, for example, by a removable cover (not illustrated here) or the like, by means of a spring 21 which is illustrated here only schematically as a helical spring. The heat conduction element 23 is in the form of a disk and is somewhat larger than the gas burner body 15, but not by too much. The heat conduction element is composed of a material which conducts heat well, for example aluminum or copper, and under certain circumstances die-cast metal.

A thermogenerator 25 is arranged on the upper face of the heat conduction element 23 such that it bears flat on said upper face, specifically such that it sits centrally on said upper face and therefore is concentric relative to the gas burner body 15. The thermogenerator 25 is in the form of a disk and is considerably thicker than the heat conduction element 23, but this does not necessarily have to be the case. Connection lines 27 of the thermogenerator are schematically illustrated and emerge from the side of said thermogenerator and are routed to an energy store 29 of the gas cooktop 11. The energy store 29 in turn is connected to the controller 20. The energy store has a rechargeable battery (not illustrated) or some other energy storage means which can be charged. Furthermore, the controller 20 can be supplied with energy not only by the energy store 29, but also directly by the thermoelectric voltage or electrical energy which is generated by the thermogenerator 25.

In order to ensure that the connection lines 27 which, as can be seen, are clearly laterally routed past the gas flames 17 have a sufficient degree of thermal resistance to said gas flames, the connection lines can have a temperature-resistant insulation. This temperature-resistant insulation can be, on the one hand, an oxide surface on a metal, which oxide surface is not electrically conductive or exhibits poor electrical conductivity, so that two metal lines or metal wires emerge from the thermogenerator 25 as connection lines 27. As an alternative, said temperature-resistant insulation can also comprise customary metal wires with a sufficiently good degree of electrical and thermal insulation due to a surrounding glass fiber fabric or the like. As an alternative, high-temperature-resistant silicone mixtures can also be added or used.

FIG. 1 also shows that the upper face of the thermogenerator 25 bears flat and directly against the lower face of a pot base 31 of a pot 30. In order to ensure effective abutment, the spring 21 is also provided. As has already been explained above, the hot side of the thermogenerator 25 is therefore also at the bottom. In this case, thermal energy is passed from the gas burner 14 or from the gas flames 17 via the heat conduction element 23 to the hot side and into the thermogenerator 25. The thermal energy is again output to the pot base 31 on the cold side which bears, on account of the spring 21, in a resilient manner and flat against the pot base 31 of the pot 30. Therefore, the thermogenerator 25 is firstly cooled by the pot base 31 to achieve the temperature difference which is required for operation. At the same time, the thermal energy is not lost to the heating process, but is actually input into the actual target, specifically the pot base 31 or the pot 30, via the diversion through the thermogenerator 25.

Similarly to the lower heat conduction element 23, a further heat conduction element can also be provided on the upper face of the thermogenerator 25, specifically in order to improve the output of the thermal energy from the thermogenerator 25 to the pot base 31. However, this actually makes sense only if this heat conduction element were considerably larger than the thermogenerator, in order to distribute the thermal energy which is output by said heat conduction element over a larger surface area of the pot base 31. Although this would improve the output of thermal energy from the thermogenerator 25 and therefore improve the degree of efficiency of said thermogenerator, it also simultaneously has an adverse effect on the input of heat from the gas burner 14 or the gas flames 17 into the pot base 31, and therefore this is actually inadvisable. Instead, the thermogenerator 25 should have a size such that it has, as is illustrated, a diameter which is somewhat smaller than the gas burner body 15 and therefore the ring of gas outlet openings 16.

The main improvement in the degree of efficiency of the thermogenerator 25 or increase in the electrical power which is generated by said thermogenerator takes place via the lower heat conduction element 23 which is, as it were, heated to a greater extent by the gas burner 14 or the gas flames 17 on account of its relatively large diameter than would be the case for the thermogenerator 25 alone. To this end, the heat conduction element 23 can, as has been described in the introductory part, have a shape which differs from a round disk in line with the ring of gas outlet openings 16. By way of example, projections and recesses in the form of a toothed wheel can be provided, with said projections and recesses advantageously being matched to the gas outlet openings 16. The gas outlet openings 16 determine, specifically, the profile of the gas flame 17. The projections can be situated exactly above the gas outlet opening 16 and therefore above the gas flames 17 in order to achieve particularly good heating. As an alternative, they can extend between said gas flames in order to be heated by them somewhat for sufficiently good introduction of thermal energy into the thermogenerator 25. At the same time, they draw some, but not too much, energy from the heating process of the pot base 31 as a result.

The spring 21, the heat conduction element 23 and the thermogenerator 25 advantageously form, together with the connection lines 27, an independent unit. Each gas burner of the gas cooktop 11 has a unit of this kind, and therefore electrical power for the energy store 29 is also generated each time a gas burner is operation, with all the thermogenerators obviously being connected to the same energy store 29 in this case.

However, in order to save on this expenditure, it is also possible to make provision for this unit to be removed from the gas burner 14 or the gas burner body 15, for example from the removable cover of said gas burner body, or else to be integrally formed with the cover. Furthermore, the connection lines 27 can be long enough to reach each gas burner of the gas cooktop. As an alternative, the connection lines 27 can be inserted and removed via detachable plug connections on the gas cooktop 11 or on the cooktop plate 12 as electrical connections.

This unit with the thermogenerator 25 is then fitted precisely to that gas burner which is intended to be operated. As a result, it is possible to ensure that electrical energy is also always generated when any gas burner of the gas cooktop 11 is burning. The electrical energy from the energy store 29 can also be used to operate the gas valve 19 which is controlled by the controller 20.

A simpler embodiment of the described gas cooktop is a refinement without a heat conduction element or a heat conduction plate. Although this may be less effective because the thermogenerator is only partially and additional non-uniformly heated, a considerably lower-cost design can be achieved on account of the saving on the heat conduction plate.

In a further alternative embodiment of a gas cooktop 111, FIG. 2 once again illustrates a gas burner 114 similar to that from FIG. 1 with a gas burner body 115, gas outlet openings 116 and gas flames 117. The gas cooktop 111 also has a thermogenerator 125 which, however, is in the form of a ring, that is to say with an opening in the middle, but this does not necessarily have to be the case. However, the thermogenerator 125 is primarily connected, radially on the outside, to the pot support arms 133, it being possible, for example as is customary, for four of these pot support arms 133 to be provided in the form of a star and form a cross together with the thermogenerator 125. The pot 130 can be placed on said thermogenerator by way of its pot base 131. Insulating parts can be provided between the thermogenerator 125 and the pot support arms 133, said insulating parts preventing thermal short-circuiting of the outer limbs of the thermogenerator by the pot support arms.

The pot support arms 133 are placed radially on the outside on pot support connection pieces 134, with insulating parts 136 being arranged between these two components. The intended result of this is that not too much thermal energy is output to the pot support connection pieces 134, and therefore to the cooktop plate 112, laterally on the outside via the pot support arms 133. The thermal energy would specifically firstly only result in interference or could cause damage in said cooktop plate. Furthermore, it would fail to heat the pot 130.

Connection lines of the thermogenerator 125, and the gas valve, the controller and the energy store according to FIG. 1 are not illustrated in FIG. 2. However, they could be provided in the same way, as can be easily imagined. Connection lines for the thermogenerator 125 can run either very close to the pot support arms 133 and the pot support connection pieces 134 and therefore also slightly removed from the gas flames 117. As an alternative, they can also run in said pot support arms and pot support connection pieces if said pot support arms and pot support connection pieces are hollow, and said connection lines are therefore very well protected.

One advantage of the arrangement in FIG. 2 is that no mechanically movable parts are necessary. However, the construction of the pot support is may be actually more complicated and a dedicated thermogenerator 125 is provided for each gas burner 114.

Furthermore, the thermogenerator 125 could also be in the form of a continuous closed disk, similarly to in FIG. 1. In a further embodiment, a heat conduction element could also be provided on the lower face again, and possibly also on the upper face, as illustrated and described in FIG. 1. It would be advantageous to provide a heat conduction element of this kind primarily on the lower face of the thermogenerator 125, that is to say, on the hot side.

FIG. 3 illustrates a further embodiment in the case of a gas cooktop 211; specifically a gas burner 214 is in the form of so-called two-ring burner in this case. The gas burner therefore has an inner gas burner 214 a and an outer gas burner 214 b, as is known in principle. The smaller inner gas burner 214 a with a gas burner body 215 a and gas outlet openings 216 a is arranged above the larger outer gas burner 214 b. However, this does not have to be the case; they could also be arranged approximately on the same plane such that they are situated concentrically one in the other.

A thermogenerator 225 with a lower heat conduction element 223 a, which is somewhat smaller and is in the form of a downwardly sloping disk, is arranged at the top of the inner gas burner 214 a or the gas burner body 215 a. The upper face, that is to say the cold side, of the thermogenerator 225 again bears flat and directly against the lower face of a pot base 231 of a pot 230 which is intended to be heated. In this case, the pot 230 is situated on the pot support connection pieces 234 which are illustrated on the outside.

The second outer gas burner 214 b has a gas burner 215 b with gas outlet openings 216 b from which large and long gas flames 217 b emerge. While the smaller gas flames 217 a of the inner gas burner 214 a at least partially act on the heat conduction element 223 or the thermogenerator 225, the outer gas flames 217 b of the outer gas burner 214 b reach only the pot base 231 or introduce thermal energy only to said pot base. The thermogenerator 225 is therefore supplied or heated only by the inner gas burner 214 a.

Similarly to FIG. 2, FIG. 3 does not illustrate the gas valves for supplying gas to the two gas burners 214 a and 214 b, the controller, the energy store and the electrical connection lines for the thermogenerator 225 either. However, they can likewise be provided as in FIG. 1. Furthermore, the thermogenerator 225 can also be arranged such that it can be either fixed to or removed from the gas burner 214 a in FIG. 3.

The operating options in respect of the two gas burners 214 a and 214 b as two-ring burners according to FIG. 3 have already been adequately discussed in the introductory part. Like the gas burners in FIGS. 1 and 2, the inner gas burner 214 a is also always intended to burn with a thermal power such that enough energy is generated for operating a control means according to FIG. 1, as far as possible also an electrically operated gas valve, in an illustrated configuration of the thermogenerator 225. However, in a two-ring burner as in FIG. 3, the major portion of the thermal energy is usually generated by the outer gas burner, and therefore the low thermal power loss due to the provision of the thermogenerator 225 is not negative.

Possible evaluation methods at the thermogenerators by the control means for temperature measurement and for pot identification have likewise already been discussed in detail above. 

1. A gas burner for a gas cooktop comprising a gas burner body, the gas burner body comprising gas outlet openings, wherein a thermogenerator is arranged above said gas burner body.
 2. The gas burner as claimed in claim 1, wherein said thermogenerator is concentric relative to said gas burner.
 3. The gas burner as claimed in claim 1, wherein said thermogenerator has the same shape as said gas burner.
 4. The gas burner as claimed in claim 1, wherein said thermogenerator is in the form of a disk.
 5. The gas burner as claimed in claim 1, wherein said thermogenerator is held above said gas burner body by resilient holding means and is pushed upward to bear against a lower face of a pot which is located above said gas burner, wherein said abutment is subject to an action of a spring force.
 6. The gas burner as claimed in claim 1, wherein said gas burner openings are arranged in one plane, and wherein said thermogenerator is arranged approximately parallel to said plane of said gas burner openings.
 7. The gas burner as claimed in claim 1, wherein a lower first heat conduction element is arranged between said gas burner body and said thermogenerator, wherein said lower first heat conduction element is in the form of a disk.
 8. The gas burner as claimed in claim 7, wherein said lower first heat conduction element is larger than said gas burner body, wherein said lower first heat conduction element projects laterally beyond said gas burner body by at least 10% of a diameter of said gas burner body.
 9. The gas burner as claimed in claim 8, wherein said lower first heat conduction element has, in its edge region, recesses in the form of incisions.
 10. The gas burner as claimed in claim 1, wherein a further upper second heat conduction element is provided on an upper face of said thermogenerator, wherein said upper second heat conduction element is in the form of a disk and is approximately the same size as said thermogenerator.
 11. The gas burner as claimed in claim 1, wherein said gas burner is in the form of a single-ring burner with a single gas burner body and a single ring of gas burner openings in said gas burner body.
 12. The gas burner as claimed in claim 1, wherein said gas burner is in the form of a two-ring burner with an inner gas burner body and an outer gas burner body, wherein said thermogenerator is arranged above said inner gas burner body.
 13. The gas burner body as claimed in claim 12, configured so that a gas flame is formed on the inner gas burner body in a manner which cannot be regulated but rather always operates with a thermal power which is designed in such a way that said thermogenerator generates a required electrical power.
 14. The gas burner as claimed in claim 13, configured so that a gas flame is formed on said outer gas burner body in a manner which can be regulated.
 15. The gas burner as claimed in claim 1, wherein said thermogenerator is part of a pot support for a pot and is arranged on said gas burner such that the thermogenerator cannot move in the vertical direction.
 16. The gas burner as claimed in claim 1, wherein said thermogenerator is designed such that the thermogenerator can be removed from said gas burner body and from said gas burner.
 17. A gas cooktop having at least one gas burner comprising a gas burner body, the gas burner body comprising gas outlet openings, wherein a thermogenerator is arranged above said gas burner body, wherein said thermogenerator has an electrical connection to a power supply of said gas cooktop, wherein said power supply is connected to a controller of said gas cooktop.
 18. The gas cooktop as claimed in claim 17, wherein said power supply has an energy store comprising a rechargeable battery.
 19. The gas cooktop as claimed in claim 17, wherein said gas cooktop has at least one electrical ignition device for igniting the at least one gas burner.
 20. The gas cooktop as claimed in claim 17, wherein said gas cooktop is designed without an electrical connection or an option of being electrically connected to a mains power supply system.
 21. The gas cooktop as claimed in claim 17, wherein said electrical power of said thermogenerator is designed to be higher than an actual power required by said controller of said gas cooktop in order to store excess electrical energy from said thermogenerator in the energy store.
 22. The gas cooktop as claimed in claim 17, wherein said gas cooktop has electronically controlled electrical gas valves for supplying gas to said gas burners, said electrical gas valves configured such that at a minimum power setting in a gas burner in the form of a two-ring burner with an inner gas burner and an outer gas burner, said inner gas burner is ignited and burns with a specific thermal power, wherein said specific thermal power is designed such that said thermogenerator generates a required electrical power for supplying an electronic controller, wherein said inner gas burner burns with a higher thermal power when said gas valve is opened further and then said outer gas burner can be ignited, and a thermal power of said outer gas burner can be regulated.
 23. A method for operating a gas cooktop comprising a gas burner, the gas burner comprising a gas burner body which has gas outlet openings, wherein a thermogenerator is arranged above said gas burner body, wherein said thermogenerator has an electrical connection to a power supply of said gas cooktop, wherein said power supply is connected to a controller of said gas cooktop, the method comprising: checking whether a pot is placed over said gas burner and has cooled a cold side of the thermogenerator, wherein the thermogenerator produces a signal have a thermoelectric voltage; and evaluating the signal by a controller of the gas cooktop to determine whether the pot is present.
 24. A method for operating a gas cooktop comprising a gas burner, the gas burner comprising a gas burner body which has gas outlet openings, wherein a thermogenerator is arranged above said gas burner body, wherein said thermogenerator has an electrical connection to a power supply of said gas cooktop, wherein said power supply is connected to a controller of said gas cooktop, the method comprising: monitoring a temperature of a pot base of a pot placed on the gas cooktop using a profile of a thermoelectric voltage at the thermogenerator; determining a phase of a constant temperature of the pot base during operation of the gas burner followed by a subsequent rapid increase in temperature of the pot base; determining by the controller of the gas cooktop that the pot placed on the gas cooktop has boiled dry; and outputting by the controller a signal to turn off the gas burner.
 25. A method for operating a gas cooktop comprising a gas burner, the gas burner comprising a gas burner body which has gas outlet openings, wherein a thermogenerator is arranged above said gas burner body, wherein said thermogenerator has an electrical connection to a power supply of said gas cooktop, wherein said power supply is connected to a controller of said gas cooktop, comprising: detecting by the controller a thermal power generated at the gas burner by a gas throughflow rate to the gas burner by detecting an open position of the gas value; comparing the thermal power with the electrical power output by the thermogenerator and based on a result of the comparison determining a temperature of a pot base that has been placed on the gas burner.
 26. The method as claimed in claim 25, wherein detected measurement variables comprising the detected thermal power and detected open position of the valve are used to regulate said cooking processes. 